The present invention relates to an improvement in gutting machines for fish, particularly trout and salmon.
Known machines for gutting fish are to a high degree constructed in view of treating fish to be further processed. Therefore, relatively moderate requirements may be made of the accuracy of the treatment performed by the machine.
For gutting trout and salmon, it is previously known machines wherein the fish is guided through the machine in swimming position by means of endless feed means such as belt or chains having vertical rotation axis and which grip the fish laterally and guide it through the machine. The fish is introduced into the gutting machine in that a spearlike means which is arranged centrally between the belts and points against the feeding direction of the fish, is treaded into the abdominal cavity through an opening exposed by cutting the fish's throat. The spear is subsequently treaded out through the anal orifice of the fish. The continuation of the spear constitutes the limitation for that part of the fish's belly being cut open by an underlying rotating circular blade.
As the fish is guided forwards by said belts, belly cutting, removal of intestines and cleaning are effected by means of a number of tools arranged one after the other in the longitudinal direction of the machine (the feeding direction of the fish) and each rotating around a horizontal rotation axis transversely of the longitudinal direction of the machine.
Some disadvantages are associated with these known machines.
Removal of the fish's blood rim constitutes a particular problem. The blood rim is protected by a strong abdominal membrane. In the known gutting machines this abdominal membrane is attempted to be removed by letting the fish pass over a rotating circular disc the circumference portion of which is formed with a number of recesses. Such a rotating circular disc is in a position to remove said abdominal membrane, but simultaneously it tears up the blood rim itself, so that it is not removed in one continuous piece. Additionally, the recesses of the circular disc will cause damages in the belly of the fish.